USPTO Patents Application 10037067

United States Patent and Trademark Office

UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office

Address: COMMISSIONER FOR PATEN TS

APPLICATION NO.

10/037,067

FILING DATE

12/21/2001

FIRST NAMED INVENTOR

David E. Clune

47384 7590 12/02/2010

RYAN, MASON & LEWIS, LLP
90 FOREST AVENUE
LOCUST VALLEY, NY 1 1560

ATTORNEY DOCKET NO. CONFIRMATION NO.

NhCRAUTER, GEORGE C

PAPER NUMBER

DELIVERY MODE

Please find below and/or attached an Office communication concerning this application or proceeding.

The time period for reply, if any, is set in the attached communication.

PTOL-90A (Rev. 04/07)

UNITED STATES PATENT AND TRADEMARK OFFICE

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES

Ex parte DAVID E. CLUNE, HANAN Z. MOLLER,
and DAVID P. SONNIER

Appeal 2009-073 12 1
Application 10/037,067
Technology Center 2400

Before JAMES D. THOMAS, JEAN R. HOMERE, and
CAROLYN D. THOMAS, Administrative Patent Judges.

HOMERE, Administrative Patent Judge.

DECISION ON APPEAL 2

1 Filed December 21, 2001. The real party in interest is LSI Logic, Corp.
(App.Br.l.)

2 The two-month time period for filing an appeal or commencing a civil
action, as recited in 37 C.F.R. § 1.304, or for filing a request for rehearing,
as recited in 37 C.F.R. § 41.52, begins to run from the "MAIL DATE"
(paper delivery mode) or the "NOTIFICATION DATE" (electronic delivery
mode) shown on the PTOL-90A cover letter attached to this decision.

Appeal 2009-007312
Application 10/037,067

I. STATEMENT OF THE CASE
Appellants appeal under 35 U.S.C. § 134(a) (2002) from the
Examiner's final rejection of claims 1-11, and 13-15. Claim 12 has been
canceled. (App. Br. 2.) We have jurisdiction under 35 U.S.C. § 6(b) (2008).
We affirm.

Appellants ' Invention
Appellants invented a method and apparatus for processing a plurality
of destination nodes of a multicast session in a data network by traversing a
circularly linked list of nodes, each containing an associated destination
address for receiving multicast data and an associated link designating a next
destination node. (Fig. 3, spec. 6, 1. 15-spec. 7, 1. 15.)

Illustrative Claim

Independent claim 1 further illustrates the invention as follows:

1. A method for identifying destination nodes of a multicast session in a
network having a plurality of nodes, comprising:

forming a circularly linked list further comprising a list of destination
nodes, each destination node having an associated destination address for
receiving multicast data and a link to a next destination node in the list for
processing;

entering the list at an initial destination node;

traversing the linked list to process each destination node, for each
destination node, sending the multicast data to the associated destination
address and using the link to determine the next destination node for
processing; and

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terminating the traversing step when all linked destination nodes have
been processed.

Prior Art Relied Upon

The Examiner relies on the following prior art as evidence of

unpatentability:

Bonomi US 6,219,352 Bl Apr. 17, 2001

Knuth, "The Art of Computer Programming", Second Edition, Vol. 1
"Fundamental Algorithms", pgs. 228-231 and 270-273, Addison- Wesley
Pub. Co. Inc. 1973.

Rejection on Appeal
The Examiner rejects claims 1-11, and 13-15 under 35 U.S.C.
§ 103(a) as being unpatentable over the combination of Bonomi and Knuth.

Appellants ' Contentions
Appellants contend that the disclosures of Bonomi and Knuth are not
properly combined to render independent claim 1 unpatentable. (App. Br. 5-
8, Reply Br. 2-5.) In particular Appellants argue that there is insufficient
rationale for combining the references to teach the storage of multicast
groups in a circularly linked list. (Brief 6.) According to Appellants, while
Knuth discusses some general advantages of a circularly linked list as an
abstract data type, the reference is silent on whether the cited list can be used
as a storage device for storing multicast groups such as those disclosed in
Bonomi. (Id.) Further, Appellants argue that even though the techniques of
multicasting and circularly linked lists are well known in the art, the fact that
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the prior art has not combined them as recited in the claims constitutes
evidence of non-obviousness. {Id. at 7-8.)

Examiner's Findings and Conclusions
The Examiner finds that one of ordinary skill would have found it
obvious to substitute Knuth's circularly linked list for Bonomi's regular
linked list to store the multicast groups therein since the circularly linked list
would allow access to the multicast data in a similar manner as with the
linked list. (Ans. 12-13.)

II. ISSUE

Have Appellants shown that the Examiner erred in combining Bonomi
and Knut to teach forming circularly-linked lists containing multicast data,
as recited in independent claim 1?

III. PRINCIPLES OF LAW

The US Supreme Court has held that "[t]he combination of familiar
elements according to known methods is likely to be obvious when it does
no more than yield predictable results." KSR Int'l Co. v. Teleflex, Inc., 550
U.S. 398, 416 (2007).

The Court further instructs that "[ojften it will be necessary for a court
to look to interrelated teachings of multiple patents; . . . and the background
knowledge possessed by a person having ordinary skill in the art, all in order

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to determine whether there was an apparent reason for combining the known
elements in a the fashion claimed by the patent at issue." Id. at 418.

Additionally, the Court instructs that "'[Rejections on obviousness
grounds cannot be sustained by mere conclusory statements. Instead, there
must be some articulated reasoning with some rational underpinning to
support the legal conclusion of obviousness' .. . however, the analysis need
not seek out precise teachings directed to the specific subject matter of the
challenged claim, for a court can take account of the inferences and creative
steps that a person of ordinary skill in the art would employ." Id. (citation
omitted) (emphasis added).

IV. FINDINGS OF FACT
The following Findings of Fact (FF) are shown by a preponderance of
the evidence.

Bonomi

1. Bonomi discloses an asynchronous transfer mode (ATM) switch that
supports multicast transmissions of data frames. (Title, abstract.) In
particular, upon receiving multicast data cells for transmission to a plurality
of output branches, a queue manager within the ATM maintains in a queue a
single copy of each of the received cells as a linked list, which contains the
processing order of the cells as well as their respective addresses, and
associated datapaths. (Col. 10, 1. 61-col. 11, 1. 5.)

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2. The queue manager maintains for each queue ID (QID) an associated
port mask through which a particular cell will be transferred to a designated
output branch. The port mask selectively identifies the output branches to
which the cells will be transmitted. (Col. 11, 11. 23-38.) The port mask
subsequently identifies the cells within a physical queue that will be
transmitted to selected output ports. (Col. 14, 11. 3-8.)

3. Upon traversing a particular cell, the queue manager deletes the cell
from the queue. (Col. 8, 11. 19-22.)

4. As each cell is received at a port, the scheduler updates a port mask
entry associated therewith to indicate that the cell needs not be transmitted to
that port any longer. (Col. 14, 11. 17-25.)

Knuth

5. Knuth discloses that one advantage of circularly-linked lists is that
they allow access into the list at any given point. (P. 270.) Knuth also
discloses that a circularly linked list can be used to represent a linear
structure since they are in some instances equivalent structures (P. 272).

V. ANALYSIS

Independent claim 1 requires, inter alia, forming circularly-linked
lists containing multicast data.

As set forth in the Findings of Fact section, Bonomi discloses storing
multicast data cells in a linked list. (FF. 1.) Further, Knuth discloses that in
some instances a circularly- linked list can be used to represent a linked list,
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and that circularly-linked lists offer the advantage of allowing for entry at
any point of the list. (FF. 5.) We agree with the Examiner that the
ordinarily skilled artisan would have readily appreciated that Bonomi's
linked list can be replaced by an equivalent circularly linked list to store the
multicast data cells therein as the circularly-linked list would offer more
flexibility by allowing for entry at any point of the list.

As set forth in the Principles of Law section above, while it is often
necessary for an Examiner to identify a reason for combining the familiar
elements obtained from the prior art in establishing a prima facie case of
obviousness, the identification of such a reason is not a sine qua non
requirement. So long as the Examiner provides an articulated reasoning
with some kind of a rational underpinning to substantiate the obviousness
rejection, such a conclusion is proper. In this case, the Examiner provided
more than just a mere conclusion of obviousness. The Examiner noted on
page 5 of the Answer that "[i]t would have been obvious to one of ordinary
skill in the art at the time the invention was made to combine the teachings
of the references since Knuth discloses that using a circularly-linked list
allows for entry into the list at any point." Such a statement suffices as an
articulated reasoning. We therefore find that the cited teachings of Bonomi
and Knuth are merely known elements that perform their ordinary functions
to predictably result in a circularly-linked list that contains multicast data
cells for transmission.

Further, even if such a reason for combining the known elements of
the cited references were not provided, we find that a person of ordinary
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skill in the art would still be readily apprised of such a rationale from the
predictable system that ensues from the proffered combination. As noted
above, the case law allows the Examiner to look to the state of the prior art
including the knowledge of the ordinarily skilled artisan to surmise such a
reason for combining the known elements of the prior art. Consequently, we
reiterate that once a person of ordinary skill in the art recognizes that the
combination of certain known elements performing their ordinary functions
yields a predictable result, the ordinarily skilled artisan will ipso facto be
apprised of the reason for combining such elements. It therefore follows that
Appellants have not shown error in the Examiner's rejection of claim 1.

Because Appellants argue the rejection of claims 1-3, 7, 8, 10, 11, 13,
and 15 as a single group, claims 2, 3, 7, 8, 10, 11, 13, and 15 fall with claim
1 in accordance with 37 C.F.R. § 41.37(c)(l)(vii).

Regarding the rejection of claim 4, Appellants argue that the
combination of Bonomi and Knuth does not teach excluding from the
multicast session a destination node of the list from the received data. (Br.
8.) According to Appellants, Bonomi' s disclosure of removing entries from
the list as each cell is transmitted does not teach or suggest removing a
destination node from the list. Id. We agree with Appellants. However, we
note that Bonomi not only discloses a mechanism for updating cell entries in
the queue to be transmitted to the nodes, but the reference also discloses a
port mask that identifies selected output ports to which to transmit the cell
entries. (FF. 2, 4.) Consequently, we find that by selecting which output
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ports to transfer the received cell data to, Bonomi teaches or suggests
excluding the non- designated ports from receiving the multicast data. It
follows that Appellants have not shown that the Examiner erred in rejecting
claim 4.

Regarding claims 5 and 6, Appellants reiterate the arguments
previously raised for the patentability of claim 4. (Id. at 9.) We addressed
those arguments in our discussion of claim 4 above, and we found them
unavailing. Further, Appellants recite the additional limitations of the cited
claims, and generally allege that the combination of Bonomi and Knuth does
not teach or suggest such limitations. In response, the Examiner finds that
Bonomi' s queue manager performs the cited functions by determining which
received data cells should be forwarded to a selection of output ports. (Ans.
17.) We note that Appellants' response does not persuasively rebut the
Examiner's rejection. Appellants are reminded that merely reciting what a
claim recites or making a general allegation of patentability is not a separate
patentability argument. See Ex parte Belinne, No. 2009-004693, slip op. at
7-8 (BPAI Aug. 10, 2009) Therefore, we find that Appellants' mere
recitation of the claim language and re-statement of the Examiner's position
without showing deficiencies therein does not constitute a persuasive
rebuttal of the Examiner's rejection. (Informative.) It follows that
Appellants have not shown error in the Examiner's rejection of claims 5
and 6.

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Regarding claim 9, Appellants argue that Bonomi's disclosure of
ordering cells within a queue based on a cell order suggests entering the
queue through the first element, and thus teaches away from entering the list
through the destination node from which the data is entered, as recited in the
claim. (Br. 9-10.) In response, the Examiner finds that Bonomi teaches the
disputed limitation as a head-pointer to the oldest entry in the queue
designating the point of entry to the destination node which initially sent the
data. (Ans. 18-19.) We agree with the Examiner that the oldest destination
node in the queue qualifies as the first element within the list or an address
of the destination node through which data can be entered and circulated in
the list. Besides, as discussed above, the substitution of Knuth's circularly
linked list for Bonomi's linked list would enable the entry of the list at any
desired node therein including the node through which data was initially
entered. It follows that Appellants did not show error in the Examiner' s
rejection of claim 9.

Since Appellants reiterate the same arguments of claim 9 for claim 15,
these claims fall together.

SUMMARY

Appellants have not have established that the Examiner erred in
rejecting claims 1-11, and 13-15 under 35 U.S.C. § 103(a) as being
unpatentable over the combination of Bonomi and Knuth. We therefore
affirm this rejection.

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Appeal 2009-007312
Application 10/037,067

No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(l)(iv) (2009).

AFFIRMED

Vsh

RYAN, MASON & LEWIS, LLP
90 FOREST AVENUE
LOCUST VALLEY, NY 11560

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